VECTOR DC MAGNETOMETERS CALIBRATION ERROR

Abstract: The calibration system for vector DC magnetometers of Nurmijarvi Geophysical Observatory (Finland) is described. It is based on a three axes reference coil system and Observatory reference magnetometer. It is shown experimentally that the system allows to determine calibrated magnetometer parameters with an error about 0.02%. One important error source-influence of non-collinearity of reference and calibrated magnetometer axes- is analyzed and value of this error is estimated. Also additional possibilities of the Observatory infrastructure are described: determination of temperature errors of magnetometer’s sensor and electronics and long-term temporal drift study of up to 9 magnetometers simultaneously